Three common used TV display systems today are cathode ray tubes (CRT), rear projection, and plasma display panels (PDP). Conventional TVs and full flat TVs adopt the CRT technology. Although the mature CRT technology has the advantages of low price, some shortcomings such as smaller display dimensions, excessive thickness, and high radiation still exit. The rear projection and PDP TV display systems overcome the high radiation by CRT, however, the rear projection TV set has a higher price. While it is not as thick as the CRT TV set for the same size of display picture, it still has a substantial thickness. The thin PDP TV set is very with high price, on the other hand, does not popularize the PDP TV sets.
In recent years the composite liquid crystal panel has become a direction many vendors are pursuing in the research of large sized liquid crystal panels. For instance, the Clarity corporation and the Pioneer corporation have introduced composite liquid crystal panels that consist of liquid crystal panels. However, on handling the seam, they still have problems. Specifically, there is a gap on the seam, which becomes an eye-sore of the whole liquid crystal screen. Hence the gap is a major bottleneck in the development of the liquid crystal panel at present.
In view of the aforesaid issues, the liquid crystal display panel (LCD panel) is used as the TV set panel. The well-developed and lower priced panels of smaller dimensions are not large enough for TV set, while the technology of larger dimension LCD panel is still not well developed and very expansive. For the display systems of smaller size (30 inches or smaller), there is a growing trend to use the LCD panel to replace the CRT display system. Thus, how to employ the existing and well-developed technologies of the LCD panel to produce a larger sized panel is a highly focused research issue.